Synchrotron X-ray diffraction study of load partitioning during elastic deformation of bovine dentin

A. C. Deymier-Black, J. D. Almer, Stuart R Stock, D. R. Haeffner, David C Dunand

Research output: Contribution to journalArticlepeer-review

40 Scopus citations

Abstract

The elastic properties of dentin, a biological composite consisting of stiff hydroxyapatite (HAP) nanoplatelets within a compliant collagen matrix, are determined by the volume fraction of these two phases and the load transfer between them. We have measured the elastic strains in situ within the HAP phase of bovine dentine by high energy X-ray diffraction for a series of static compressive stresses at ambient temperature. The apparent HAP elastic modulus (ratio of applied stress to elastic HAP strain) was found to be 18 ± 2 GPa. This value is significantly lower than the value of 44 GPa predicted by the lower bound load transfer Voigt model, using HAP and collagen volume fractions determined by thermo-gravimetric analysis. This discrepancy is explained by (i) a reduction in the intrinsic Young's modulus of the nano-size HAP platelets due to the high fraction of interfacial volume and (ii) an increase in local stresses due to stress concentration around the dentin tubules.

Original languageEnglish (US)
Pages (from-to)2172-2180
Number of pages9
JournalActa Biomaterialia
Volume6
Issue number6
DOIs
StatePublished - Jun 2010

Keywords

  • Collagen
  • Dentin
  • Hydroxyapatite
  • Mechanical properties
  • X-ray diffraction

ASJC Scopus subject areas

  • Biotechnology
  • Biomaterials
  • Biochemistry
  • Biomedical Engineering
  • Molecular Biology

Fingerprint Dive into the research topics of 'Synchrotron X-ray diffraction study of load partitioning during elastic deformation of bovine dentin'. Together they form a unique fingerprint.

Cite this